In a large mixing bowl sift the flour and salt together. Cut or rub in the shortening very quickly, until the mixture resembles cornmeal. Add the ice water and toss the pastry together with a fork, stirring to the center until the pastry forms a ball. (Do not work the pastry). Divide the pastry into 2 parts, form each into a ball, wrap in plastic, and chill at least 1 hour.

Roll 1 ball to a thickness of 1/8 inch and line a 10-inch pie plate with it. (Wrap tightly and freeze the other ball for late use.)

Preheat the oven to 375 degrees.

Cream the margarine and sugar together gradually in a large mixing bowl and beat until blended. Add the corn syrup and salt and mix well. Add the eggs, 1 at a time, beating well after each addition. Stir in the chocolate bits, walnuts, vanilla and bourbon. Pour the filling into the pie shell and bake 40 to 50 minutes.